The present invention relates to the general field of aircraft, and in particular to civil airplanes, which aircraft are propelled by a bypass turbojet incorporated in part in the fuselage of the aircraft.
Civil airplanes are generally fitted with turbojets mounted under the wings or in a rear position on the fuselage, and they are fastened thereto by means of pylons.
Because of the increase in the cost of fuel expected in the years to come, engine manufacturers are seeking to reduce the fuel consumption of civil airplanes. One of the ways envisaged for doing this is to embed the engines at least in part inside the fuselage of an airplane in order to eliminate the pylons and the fairings of the engines, thereby reducing the weight of the propulsion unit and reducing its drag. The sound nuisance from the airplane is also reduced thereby.
Furthermore, in flight, a boundary layer forms around the fuselage of the airplane and generates aerodynamic drag. In the past, although it used to be considered that engines should not ingest this boundary layer in order to avoid high levels of distortion in the fan and high levels of vibration in the shafts of the engines, it is now considered that taking a portion of this boundary layer into the engines makes it possible to reduce the aerodynamic drag of the airplane and to reduce the speed with which air is admitted into the engines, thereby achieving a significant improvement in propulsion efficiency.
Thus, Document WO 2010/049610 describes an airplane architecture having engines with nacelles that are partially embedded in the fuselage of the airplane in order to take in a portion of the boundary layer.